Answer
The equation expressing E and M is $E=2.4M-20$.
Work Step by Step
The relation between Elvis(E) and Madonna(M) can be expressed as follows
$E=aM+c$
Substitute the given values in the above relation
$40=a\left( 25 \right)+c$ (I)
$280=a\left( 125 \right)+c$ (II)
Subtract equation (II) from equation (I):
$\begin{align}
& -240=a\left( -100 \right) \\
& \frac{-240}{-100}=a \\
& a=2.4
\end{align}$
Now, substitute the value of “a” in (I)
$\begin{align}
& 40=a\left( 25 \right)+c \\
& 40=\left( 2.4 \right)\left( 25 \right)+c \\
& 40=60+c \\
& c=-20
\end{align}$
Thus, the equation between E and M will be $E=2.4M-20$.
